The fire reportedly started after a huge Chinese lantern landed on the roof of the building, with the fire spreading quickly in the roof area. Debris and smoke left one end of the track blackened and damaged, with the track centre flooded as fire fighters fought to put out the blaze.

There were no reports of injuries because the fire hit during the night. The full damage is being evaluated.

Brazil's sports minister, Leonardo Picciani, confirmed the incident on Twitter and posted videos of further Chinese lanterns or balloons falling near the site inside the Olympic Park. He wrote: "Absurd! In addition to the balloon that burned the velodrome, other balloons fell in the Olympic Park" with a photo showing several of the Chinese lanterns.

The huge cost of the 2016 Rio Olympics for Brazil and the rapid damage to other Olympic sites has already sparked anger. The velodrome only reopened in May but will now need some major work to make the building and track surface safe to use.

A government statement condemned the use of the Chinese lanterns and promised to repair the damage to the velodrome.

"The Ministry of Sport deeply regrets the incident this morning at the Velodrome Park and at the same time criticises this criminal practice of releasing balloons," the statement reads.

"The velodrome, a legacy of the Brazilian Olympic Games, was used by athletes and the community of Rio de Janeiro. We await and rely on the punishment of those involved for destroying more than a public good, a common site for all.

"After the fire brigade, we will assess the damage and measures to be taken to recover this important national asset."